1. Field of the Invention
The invention generally relates to accelerometers, and more particularly to a motion detection device, including a pendulum switch, having particular utility in burglar alarm systems and the like.
2. Description of the Prior Art
The prior art is, of course, replete with accelerometers adapted to detect motion imparted in given directions to given bodies, both bodies in motion and bodies at rest. Of course, the configuration and design of such devices vary substantially. However, motion detection devices relied upon for purposes of indicating the presence of intruders and the like normally include circuitry adapted to respond to an interruption of circuit continuity resulting from unauthorized entry, such as through a breaking of circuits painted on glass panes and the like. In most instances, motion detection devices suitably sensitive for detecting motion resulting from the presence of intruders gaining entry through stealth are relatively economically expensive to fabricate and are complicated to install and maintain.
As can be appreciated by owners of homes, small shops, and the like, it often is economically impractical to attempt to secure structures employing existing intruder detection systems having suitable sensitiveness for detecting intruders who do not literally break into the structure.
Furthermore, fire detection systems normally require heat-responsive devices adapted to be activated for indicating the existence of a detected fire. Such devices are used even though heated air currents normally are generated and attend fires occurring in buildings and the like, as a consequence of the air within the building being expanded, before the heat sensitive devices employed for detecting the existence of a fire are activated.
It is, therefore, the general purpose of the instant invention to provide a motion detection device, the sensitiveness of which can be adjusted, and which is economic to fabricate, simple to install and maintain and suitably sensitive for use in detecting motion of structure as well as streams of air within buildings and the like, whereby motion resulting from the presence of intruders, the existence of fires and similar catastrophic occurrences readily can be detected for providing an alarm.